The subject invention is directed toward the art of gauge glass devices and, more particularly, to an improved arrangement for mounting a gauge glass shield. The invention is especially suited for use in gauge glass shields of the type used in coffee beverage makers, such as urns and percolators, and will be described with reference thereto; however, it will be appreciated that the invention is capable of broader application.
In particular, the invention contemplates the provision of a gauge glass assembly comprising an upwardly open receptor, with a guage glass tube having its lower end positioned in the receptor and extending upwardly therefrom. A tubular shield surrounds the gauge glass member and has a length at least nearly as long as the gauge glass. Means are provided in the shield to permit visual observation of the gauge glass. An upper nut member is threaded on the upper end of the shield member and includes a portion engaged with the upper end of the gauge glass such that tightening of the upper nut member on the shield applies an axial force to the gauge glass to drive it toward the receptor. A lower nut member is carried about the lower end of the shield and threaded to the receptor. Interengaging portions are provided between the second nut member and the shield such that tightening of the lower nut member causes the shield to be driven axially toward the receptor. Preferably, the interengaging portions between the lower nut member and the shield comprise outwardly extending tabs or ears included on the shield and extend outwardly under a flange formed on the lower nut.
According to a somewhat limited aspect of the invention, the tabs are an integral part of the shield and are formed by deforming a portion of the shield. Specifically, the tabs are formed by a staking operation to deform outwardly a portion of the shield tube at the lower end of the elongated opening.
In accordance with a further aspect of the invention, the receptor includes a resilient seal surface which engages the lower end of the gauge glass to provide a fluid seal. Preferably, the seal surface is located such that tightening of the first nut member drives the gauge glass into tight engagement with the sealing surface.
In accordance with another aspect of the present invention, the gauge glass and shield comprise a single tubular member.
Accordingly, a primary object of the invention is the provision of a simplified gauge glass and shield assembly.
Another object is the provision of a gauge glass assembly having a shield member arranged to hold the gauge glass trapped between resilient washers at its opposite ends.
A further object of the invention is the provision of an assembly of the type described wherein the gauge glass and shield are releasably held in position through tabs or ears formed on the shield.